Apple is expected to introduce a new iPhone in September with a new, tougher sapphire display.

Tim Bajarin, an independent analyst with Creative Strategies, says sapphire is very expensive to produce, and will add $100 to the cost of the new iPhone. He believes Apple will offer it as a step-up upgrade for folks who want a stronger, more scratch-resistant screen. The iPhone with its current Gorilla Glass screen will continue to be offered at the same price, he says.

With sapphire, the benefit for consumers is obvious, if you believe the many online-rumor videos. Several folks claim to have gotten a sample and have tried to scratch and destroy it, to no avail.

"We don't have to use screen protectors any more," says YouTube tech reviewer Marques Brownlee, whose video purporting to show a leaked sample of a sapphire iPhone screen has raked in over 7 million views.

Unlike Gorilla Glass, Sapphire isn't really glass, nor is it derived from the blue gem. In fact, it's been described to me by Matthew Hall, an associate professor of Glass Science at Alfred University, as a see-through ceramic material.

It derives from chemically pure oxide powder, which is then melted into single crystal sapphire ceramic at the factory, and then mass produced.

Sapphire is the toughest substance out there, used by aircrafts and the military. "It's not like you can drive a car over it," says Hall. "But it will do better than traditional glass."

Sapphire is currently in use on iPhones on the home button's fingerprint scanner and as a cover for the built-in camera. A company in Mesa Ariz., GT Advanced Technologies, is mass-producing sapphire for Apple at its 1.3 million square foot facility, where independent analyst Richard Doherty of the Envisioneering Group says it's also working on Apple's upcoming wearable health device.

Doherty says Apple has quietly amassed the largest supply of sapphire on the planet, a process that has taken several years.

Sapphire, he believes, is so strong, "You'll see next season some TV show where someone is about to be shot, and he holds up his iPhone for protection, to stop the bullet from entering the body."

Due to the epidemic of shattered smartphone screens, which break easily when dropped on the ground, many companies have built large businesses fixing smartphone screens. If sapphire is as strong as some folks suggest, what will that do to their business?

"The jury is out on how impact resistant these screens are," says Anthony Martin, the co-founder of iCracked.com, which fixes smartphone screens. "If they are to break, we'll be there to help fix those quickly."